FIG. 10 is a perspective view showing a conventional cutting machine disclosed in Japanese Utility Model Publication NO. 33297/90. Referring to the Figure, designated at 200 is the cutting machine as a whole, at 201 a laser, at 202 a laser beam output therefrom, at 203 a laser beam scanner for reflecting the laser beam 202 from the laser 201 such as to scan a desired position of a feed conveyer 205 confined in a machining chamber 204 with the reflected laser beam 202, at 206a, 206b two ITV cameras for taking pattern images, at 207 a monitor for displaying images taken by the ITV cameras 206a and 206b, at 208 a digitizer for moving a cursor on the monitor 207, at 209 a position matching controller for controlling the image input and the digitizer 208, and at 210 a cutting machine controller for controlling the cutting machine 200. The position matching controller corrects cutting data, the corrected cutting data being input to the cutting machine controller 210. Designated at 211 is an illumination unit for making clear the images of workpiece taken by the ITV cameras 206a and 206b,
The position matching controller 209 controls the ITV cameras 206a and 206b and digitizer 208. The ITV cameras 206a and 206b, digitizer 208 and monitor 207 are connected to the position matching controller 209. When position matching is done by the operator, the position matching controller 209 produces correction data according to the position matching operation and outputs the correction data to the cutting machine controller 210. The cutting machine controller controls the laser 201 and the laser beam scanner 203 for the execution of cutting of workpiece according to cutting data produced with a CAD or the like and corrected cutting data obtained after correction by the correction data noted above.
The operation of the cutting machine 200 will now be described with reference to FIG. 11. As shown, the top of the feed conveyer 205 is divided into a "developed piece position matching region", a "cutting region" and a "take-out region", the "cutting region" being located in the process chamber 204. The ITV cameras 206a and 206b are disposed above the "developed piece pattern matching region". The workpiece 212 is fed on the feed conveyor 205 in the direction of arrow past the "developed piece pattern matching region", "cutting region" and "take-out region".
The workpiece 212 is set on the feed conveyer 205 at a predetermined position thereof in the "developed piece pattern matching region" before being fed to the "cutting region". Beneath the ITV cameras 206a and 206b, a predetermined range of the workpiece 212 is photographed with the ITV camera 206a by holding the feed conveyer 205 for a while. The image of the workpiece range thus obtained is displayed on the monitor 207.
At the same time, a cursor indicating a predetermined position matching reference position on the monitor screen is also displayed. This cursor is displayed according to the cutting data, and normally it is displayed at the center of the screen of the monitor 207. The operator moves the cursor on the screen of the monitor 207 to the position matching position of the workpiece 212 by operating the cursor switch in the digitizer 208. According to the movement of the displayed cursor, the position matching controller 209 calculates "first correction data" to be stored in a memory.
Then, the input to the monitor 207 is switched, and a predetermined range of the workpiece 212 is photographed with the other ITV camera 206b. The image of the range thus obtained is displayed on the monitor 207. Then, "second correction data" is calculated and stored in the memory in the manner as noted above.
The position matching controller 209 corrects the cutting data given by the CAD or the like according to the "first correction data" and "second correction data". The correction is effected with parallel movement, rotation or a combination of these motions. When the position matching operation is completed, the workpiece 212 is moved on the feed conveyer 205 into the process chamber 204. Then, cutting is executed according to the corrected cutting data. The workpiece 212 after the cutting is fed on the feed conveyer 205 to the "take-out region". The position matching and cutting are executed by repeating like operations.
As for a part pick-up technique related to this type of the cutting machine, there is one in which parts are picked up with gripping means. In this gripping type parts pick-up system, a plurality of gripping mechanisms are controlled by determining gripping conditions from the size of parts and positional relation thereof to the gripping mechanisms. In the pick-up operation, the feed conveyer is stopped a plurality of times to effect the pick-up of parts.
As other reference literatures pertaining to the present invention, there are "Next Step Feed System in Clothing Sewing Process and Apparatus for the Same" disclosed in Japanese Patent Laid-Open No. 49991/92, "Automatic Cutting Apparatus" disclosed in Japanese Patent Laid-Open No. 281079/91, "Pattern Matching Cutting Apparatus" disclosed in Japanese Patent Laid-Open No. 24278/92, "Method and Apparatus for Pattern Matching Base Material" disclosed in Japanese Patent Laid-Open No. 240261/92, "Cutting Table Protection Sheet for Automatic Cutting Machine" disclosed in Japanese Utility Model Laid-Open NO. 33597/89, "Workpiece Pick-Up device" disclosed in Japanese Patent Laid-Open No. 108489/92, and "Workpiece Feeding Device of Cutting Apparatus" disclosed in Japanese Patent Laid-Open No. 178320/86.
In the conventional cutting machine described above, the feeding of workpiece, pick-up of parts and removal of cutting remains were all done manually. In addition, since the gripping system was adopted as the parts pick-up means, it was necessary to stop the feed conveyer a plurality of times in an interlocked relation to the pick-up process. Therefore, the production efficiency was inferior. Further, with the conventional gripping system, a deviation of the workpiece is generated on the feed path, thus disabling accurate pick-up of parts and hence disabling accurate cutting process.